Access System, Communication Method and Device for Optical Fiber Network

ABSTRACT

Embodiments of the present invention provide an access system and a communication method for an optical fiber network. A virtual ONU located on a user side is established, and an ONU control plane function, a PON MAC function, and a QoS function on an existing ONU is moved downwards to a virtual ONU. After the forgoing function modules are removed from the existing ONU, the existing ONU becomes an ONU physical converter and only has a function of converting the PON physical layer frame and the first user side physical layer frame.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. application Ser. No.14/322,574, filed on Jul. 2, 2014, which is a continuation ofInternational Application No. PCT/CN2012/079767, filed on Aug. 7, 2012,which is hereby incorporated by reference in its entirety.

TECHNICAL FIELD

The present invention relates to the field of communications and, inparticular embodiments, to an access system, a communication method anda device for an optical fiber network.

BACKGROUND

Because an optical fiber has a higher transmission speed and users haveincreasingly high requirements on bandwidth, it has become a developmenttrend for an access network to replace a cable with the optical fiber.FTTH (Fiber To The Home) is a future development direction. However,direct fiber to the home requires re-laying out an optical fiber foreach home, which has high costs. Therefore, FTTDp (Fiber ToDrop/Distribution Point) is still used for a long time. A copper cable(such as a phone twisted pair cable, a cable TV cable, a power cable, oran Ethernet network cable) that has been connected into the user's houseor a wireless interface connection is still used in the last distanceinto the user's house for the connection of the optical fiber to anexternal wall of a family house

An access system of an existing optical fiber network mainly includes anONU (Optical Network Unit) and an OLT (Optical Line Termination), wherethe OLT is connected to the ONU through an optical fiber and isconfigured to send downstream data to the ONU or receive upstream datafrom the ONU. The ONU can complete a PON (Passive Optical Network) MAC(Media Access Control) function, an ONU control plane function, and aQoS (Quality of Service) function for the optical fiber network. The ONUcan be connected to a CPE (Customer Premise Equipment) through thecopper cable that has been connected into the user's house or throughthe wireless interface connection.

However, in the access system of the existing optical fiber network, theONU is a device provided by a carrier. In a fiber to drop/distributionpoint scenario, the ONU needs to be deployed in a place near to a userside but far from a carrier's network (for example, deployed in theexternal wall of the family house). A large number of ONUs exist and theONU needs to complete many functions such as the PON MAC function, theONU control plane function and the QoS function. Therefore, in the caseof massive ONUs on the optical fiber network, it is very difficult tomaintain the ONUs on the optical fiber network and a maintenance cost isvery high.

SUMMARY

To solve the problems of great difficulty and high cost in maintainingONUs in an access system of an existing optical fiber network,embodiments of the present invention provide an access system, acommunication method and a device for an optical fiber network.Technical solutions are as follows.

An access system for an optical fiber network is provided. An OLT isconfigured to assign an upstream time slice and a downstream time slicefor each customer premises equipment connected to the optical fibernetwork. An ONU physical converter is connected to the OLT through anoptical fiber and is configured to receive a PON physical layer framewhich is sent by the OLT through a PON physical signal, to convert thePON physical layer frame to a first user side physical layer framecorresponding to a non-PON physical signal, to send the first user sidephysical layer frame to the customer premises equipment through thenon-PON physical signal, to receive a first user side physical layerframe which is sent by the customer premises equipment through thenon-PON physical signal, to convert the first user side physical layerframe to a PON physical layer frame corresponding to the PON physicalsignal, and to send the PON physical layer frame to the OLT through thePON physical signal. The customer premises equipment is connected to theONU physical converter through a non-PON optical fiber and located on auser side and is configured to realize an ONU control plane function anda PON MAC function, and to send the first user side physical layer frameto the OLT according to the upstream time slice through the ONU physicalconverter or receive. According to the downstream time slice, the firstuser side physical layer frame which is sent by the OLT through the ONUphysical converter.

The access system further includes a POS (Passive Optical Splitter),configured to receive the PON physical signal sent by the OLT, assignand send the PON physical signal to different ONU physical converters.

A communication method based on the forgoing system is provided. Acustomer premises equipment reports a data queue state to an OLT throughan ONU physical converter. The OLT assigns an upstream time slice and adownstream time slice to the customer premises equipment and sendsconfiguration information which includes the upstream time slice and thedownstream time slice to the customer premises equipment through the ONUphysical converter. The customer premises equipment sends upstream datato the OLT through the ONU physical converter or receives downstreamdata from the OLT according to the configuration information.

Before the customer premises equipment reports the data queue state toan OLT through an ONU physical converter, the method further includesthe following steps. The customer premises equipment receives a secondphysical layer parameter which is delivered by the OLT through the ONUphysical converter. The customer premises equipment establishes a newcommunication connection with the ONU physical converter according tothe second physical layer parameter delivered by the OLT.

Before the customer premises equipment receives the second physicallayer parameter which is delivered by the OLT through the ONU physicalconverter, the method further includes the following steps. The customerpremises equipment establishes a communication connection with the ONUphysical converter according to a default first physical layerparameter. The customer premises equipment establishes a communicationconnection with the OLT, where the default first physical layerparameter is reserved on the customer premises equipment and the ONUphysical converter.

After the sending, by the customer premises equipment, according to theconfiguration information, upstream data to the OLT through the ONUphysical converter or receiving downstream data from the OLT, the methodfurther includes the following step. The customer premises equipmentreports a physical line state of the communication connection with theOLT to the OLT through the ONU physical converter.

After the customer premises equipment sends the upstream data to the OLTthrough the ONU physical converter or receives downstream data from theOLT according to the configuration information, the method furtherincludes the following steps. The OLT establishes a request to increasebandwidth for temporary communication of a user, reassigning bandwidthto the customer premises equipment, and delivers a third physical layerparameter to the customer premises equipment through the ONU physicalconverter according to current bandwidth assignment. The customerpremises equipment establishes a new communication connection with theONU physical converter according to the third physical layer parameter,and obtaining the reassigned bandwidth. The OLT restores bandwidth forthe customer premises equipment when the temporary communication ends.

Further, the OLT restores the bandwidth for the customer premisesequipment specifically by doing the following. The OLT delivers thesecond physical layer parameter to the customer premises equipmentthrough the ONU physical converter. The customer premises equipmentre-establishes a communication connection with the ONU physicalconverter according to the second physical layer parameter. The customerpremises equipment re-establishes a communication connection with theONU physical converter, so that the customer premises equipment restoresthe bandwidth before the temporary communication.

A customer premises equipment is provided, where the customer premisesequipment is connected to an ONU physical converter through a non-PONoptical fiber and is located on a user side, and is configured torealize an ONU control plane function and a PON MAC function, send,according to an upstream time slice assigned by an OLT, a first userside physical layer frame to the OLT through the ONU physical converter,or receive, according to a downstream time slice assigned by the OLT, afirst user side physical layer frame which is sent by the OLT throughthe ONU physical converter.

Further, the customer premises equipment is further configured toreceive a second physical layer parameter which is delivered by the OLTthrough the ONU physical converter and establish a new communicationconnection with the ONU physical converter according to the secondphysical layer parameter delivered by the OLT.

Further, the customer premises equipment is further configured to:before receiving the second physical layer parameter which is deliveredby the OLT through the ONU physical converter, establish a communicationconnection with the ONU physical converter according to a default firstphysical layer parameter and establish a communication connection withthe OLT, where the default first physical layer parameter is reserved onthe customer premises equipment.

Further, the customer premises equipment is further configured to reporta physical line state of the communication connection with the OLT tothe OLT through the ONU physical converter.

Further, the customer premises equipment specifically includes thefollowing. A user side interface unit is configured to receive anupstream second user side physical layer frame sent by a user or send adownstream second user side physical layer frame to the user. A virtualONU processing unit is configured to realize the ONU control planefunction, the PON MAC function, and a quality of service QoS function,encapsulate the upstream second user side physical layer frame into anupstream PON MAC layer frame, send the upstream PON MAC layer frame tothe ONU physical converter through a user side physical layer processingunit according to the upstream time slice assigned by the OLT orreceive, according to the downstream time slice assigned by the OLT, adownstream PON MAC layer frame sent by the user side physical layerprocessing unit, convert the downstream PON MAC layer frame to thedownstream second user side physical layer frame, and send thedownstream second user side physical layer frame to the user sidephysical layer processing unit through the user side interface unit.

The user side physical layer processing unit is configured to convertthe upstream PON MAC layer frame sent by the virtual ONU processing unitto an upstream first user side physical layer frame corresponding to anon-PON physical signal and send the upstream first user side physicallayer frame to the ONU physical converter through the non-PON physicalsignal, to receive a downstream first user side physical layer framesent by the ONU physical converter, to convert the downstream first userside physical layer frame to the downstream PON MAC layer frame, and tosend the downstream PON MAC layer frame to the virtual ONU processingunit.

Further, the customer premises equipment further includes a customerpremises equipment CPE unit. The CPE unit is connected to the user sideinterface unit and a user equipment UE and is configured to receive thedownstream second user side physical layer frame sent by the user sideinterface unit and forward the downstream second user side physicallayer frame to the UE, or receive upstream data sent by the UE, convertthe upstream data to the upstream second user side physical layer frame,and send the upstream second user side physical layer frame to the userside interface unit.

The customer premises equipment further includes the following. Anexternal power supply unit is configured to provide power for the ONUphysical converter. An ONU physical converter is connected to the OLTthrough an optical fiber, and configured to receive a PON physical layerframe which is sent by the OLT through a PON physical signal, convertthe PON physical layer frame to a first user side physical layer framecorresponding to the non-PON physical signal, and send the first userside physical layer frame to the customer premises equipment through thenon-PON physical signal; or receive a first user side physical layerframe which is sent by the customer premises equipment through thenon-PON physical signal, convert the first user side physical layerframe to a PON physical layer frame corresponding to the PON physicalsignal, and send the PON physical layer frame to the OLT through the PONphysical signal.

Further, the ONU physical converter is further configured to forward tothe customer premises equipment the second physical layer parameterdelivered by the OLT and establish the new communication connection withthe customer premises equipment according to the second physical layerparameter delivered by the OLT.

Further, the ONU physical converter is configured to establish thecommunication connection with the customer premises equipment accordingto the default first physical layer parameter before the customerpremises equipment receives the second physical layer parameter which isforwarded by the OLT through the ONU physical converter. The defaultfirst physical layer parameter is reserved on the customer premisesequipment.

Further, the ONU physical converter is configured to forward to the OLTthe physical line state of the communication connection reported by thecustomer premises equipment.

Further, the ONU physical converter includes a non-PON physical layerprocessing unit, a switch control unit, a switch unit, and a PONphysical layer processing unit. The non-PON physical layer processingunit is configured to receive the upstream first user side physicallayer frame which is sent by the customer premises equipment through thenon-PON physical signal and convert the upstream first user sidephysical layer frame to the upstream PON MAC layer frame. The switchcontrol unit is configured to receive the upstream PON MAC layer framewhen sent by the customer premises equipment, generate a switch controlsignal corresponding to the customer premises equipment and send theswitch control signal corresponding to the customer premises equipmentto the switch unit. The switch unit, including one output interface andat least one input interface where there is one-to-one correspondencebetween the input interface and the customer premises equipmentconnected to the ONU physical converter, is configured to connect,according to the switch control signal corresponding to the customerpremises equipment, a channel between an input interface correspondingto the customer premises equipment and an output interface, where thechannel is configured for the non-PON physical layer processing unit tosend the upstream PON MAC layer frame obtained through conversion by thenon-PON physical layer processing unit to the PON physical layerprocessing unit. The PON physical layer processing unit is configured toconvert the upstream PON MAC layer frame to an upstream PON physicallayer frame and send the upstream PON physical layer frame to the OLTthrough the PON physical signal.

Further, the ONU physical converter includes a non-PON physical layerprocessing unit, an Ethernet bridge, and a PON physical layer processingunit. The non-PON physical layer processing unit is configured toreceive the upstream first user side physical layer frame which is sentby the customer premises equipment through the non-PON physical signal,convert the upstream first user side physical layer frame to theupstream PON MAC layer frame, and send the upstream PON MAC layer frameto the Ethernet bridge through an input interface corresponding to thenon-PON physical layer processing unit. The Ethernet bridge, includingone output interface and at least one input interface, is configured toreceive the upstream PON MAC layer frame which is sent by the non-PONphysical layer processing unit through the input interface and send theupstream PON MAC layer frame to the PON physical layer processing unitthrough the output interface. The PON physical layer processing unit isconfigured to receive the upstream PON MAC layer frame which is sent bythe Ethernet bridge through the output interface, convert the upstreamPON MAC layer frame to the upstream PON physical layer frame, and sendthe upstream PON physical layer frame to the OLT through the PONphysical signal.

Further, the ONU physical converter includes a PON physical layerprocessing unit, a non-PON physical layer processing unit, andinterfaces respectively corresponding to customer premises equipmentconnected to the ONU physical converter, and a downstream datareplicating unit. The PON physical layer processing unit is configuredto receive a downstream PON physical layer frame which is sent by theOLT through the PON physical signal and convert the downstream PONphysical layer frame to a downstream PON MAC layer frame. The interfacesare configured respectively to connect lines between the downstream datareplicating unit and the non-PON physical layer processing unit, wherethe lines are configured to send the downstream PON MAC layer frameobtained through conversion by the PON physical layer processing unit tothe non-PON physical layer processing unit. The downstream datareplicating unit is configured to replicate the downstream PON MAC layerframe obtained through conversion by the PON physical layer processingunit to all lines which belong to the ONU physical converter. Thenon-PON physical layer processing unit is configured to convert thedownstream PON MAC layer frame to a downstream first user side physicallayer frame and send the downstream first user side physical layer frameto the customer premises equipment through the non-PON physical signal.

Further, the ONU physical converter includes a PON physical layerprocessing unit, an Ethernet bridge, and a non-PON physical layerprocessing unit. The PON physical layer processing unit is configured toreceive the downstream PON physical layer frame sent by the OLT, convertthe downstream PON physical layer frame to the downstream PON MAC layerframe, add an Ethernet broadcast frame header to the downstream PON MAClayer frame to obtain an Ethernet frame, and send the Ethernet frame tothe Ethernet bridge. The Ethernet bridge, including one input interfaceand at least one output interface, is configured to receive, through theinput interface, the Ethernet frame sent by the non-PON physical layerprocessing unit and send the Ethernet frame to the PON physical layerprocessing unit through the output interface. The non-PON physical layerprocessing unit is specifically configured to receive the Ethernet framewhich is sent by the Ethernet bridge through the output interface,remove the Ethernet broadcast frame header from the Ethernet frame toobtain the downstream PON MAC layer frame, convert the downstream PONMAC layer frame to the downstream first user side physical layer frame,and send the downstream first user side physical layer frame to thecustomer premises equipment through the non-PON physical signal.

The technical solutions provided in embodiments of the present inventionhave the following beneficial effects. The customer premises equipmentis established, the ONU control plane function, the PON MAC function,and the QoS function on the existing ONU are moved downwards to theestablished customer premises equipment. After the forgoing functionsare removed from the existing ONU, the existing ONU becomes the ONUphysical converter and only has a function of converting the PONphysical layer frame and the first user side physical layer frame.Therefore, a carrier does not need to maintain the ONU control planefunction, the PON MAC function, and the QoS function, which lowersmaintenance complexity and greatly reduces maintenance costs.

BRIEF DESCRIPTION OF THE DRAWINGS

To illustrate the technical solutions in the embodiments of the presentinvention more clearly, the following briefly introduces theaccompanying drawings required for describing the embodiments of thepresent invention. Apparently, the accompanying drawings in thefollowing description show merely some embodiments of the presentinvention, and a person of ordinary skill in the art may still deriveother drawings from these accompanying drawings without creativeefforts.

FIG. 1 is a schematic structural diagram of an access system for anoptical fiber network provided by Embodiment 1 of the present invention;

FIG. 2 is an integrated schematic structural diagram of a customerpremises equipment provided by Embodiment 1 of the present invention;

FIG. 3 is a second schematic structural diagram of an access system foran optical fiber network provided by Embodiment 1 of the presentinvention;

FIG. 4 is a schematic diagram of a protocol stack of a new access systemfor an optical fiber network provided by Embodiment 2 of the presentinvention in a case where an Ethernet bridge is not used;

FIG. 5 is a schematic diagram of a protocol stack of a new access systemfor an optical fiber network provided by Embodiment 2 of the presentinvention in a case where an Ethernet bridge is used;

FIG. 6 is a schematic diagram of an access system for an optical fibernetwork that requires no configuration of an ONU physical converterprovided by Embodiment 2 of the present invention;

FIG. 7 is another schematic diagram of an access system for an opticalfiber network that requires no configuration of an ONU physicalconverter provided by Embodiment 2 of the present invention;

FIG. 8 is a schematic flowchart of a communication method based on anaccess system for an optical fiber network provided by Embodiment 2 ofthe present invention;

FIG. 9 is a schematic flowchart of a method for adjusting bandwidthonline based on an access system for an optical fiber network providedby Embodiment 2 of the present invention;

FIG. 10 is a schematic structural diagram of a customer premisesequipment provided by Embodiment 3 of the present invention;

FIG. 11 is a second schematic structural diagram of a customer premisesequipment provided by Embodiment 3 of the present invention;

FIG. 12 is a third schematic structural diagram of a customer premisesequipment provided by Embodiment 3 of the present invention;

FIG. 13 is a schematic structural diagram of an ONU physical converterprovided by Embodiment 4 of the present invention;

FIGS. 14A-14B is a schematic construction diagram of an access systemfor an optical fiber network provided by Embodiment 4 of the presentinvention;

FIG. 15 is a schematic diagram for correspondence between user sideinterfaces and a switch control signal and a PON optical module stateprovided by Embodiment 4 of the present invention;

FIG. 16 is a second schematic structural diagram of an ONU physicalconverter provided by Embodiment 4 of the present invention;

FIGS. 17A-17B is a second schematic construction diagram of an accesssystem for an optical fiber network provided by Embodiment 4 of thepresent invention;

FIG. 18 is a third schematic structural diagram of an ONU physicalconverter provided by Embodiment 4 of the present invention; and

FIGS. 19A-19B is a third schematic construction diagram of an accesssystem for an optical fiber network provided by Embodiment 4 of thepresent invention.

DETAILED DESCRIPTION OF ILLUSTRATIVE EMBODIMENTS

To make the objectives, technical solutions, and advantages of thepresent invention more clearly, the following further describes theembodiments of the present invention in detail with reference to theaccompanying drawings.

Embodiment 1

As shown in FIG. 1, this embodiment provides an access system for anoptical fiber network, where the system includes the following. An OLT11is configured to assign an upstream time slice and a downstream timeslice for each customer premises equipment connected to the opticalfiber network.

An ONU physical converter 12 is connected to the OLT11 through anoptical fiber, and configured to receive a PON physical layer framewhich is sent by the OLT11 through a PON physical signal, convert thePON physical layer frame to a first user side physical layer framecorresponding to a non-PON physical signal, and send the first user sidephysical layer frame to a customer premises equipment 13 through thenon-PON physical signal, or receive a first user side physical layerframe which is sent by the customer premises equipment 13 through thenon-PON physical signal, convert the first user side physical layerframe to a PON physical layer frame corresponding to the PON physicalsignal, and send the PON physical layer frame to the OLT11 through thePON physical signal.

The customer premises equipment 13 is connected to the ONU physicalconverter 12 through a non-PON optical fiber and located on a user side,and configured to realize an ONU control plane function, a PON MACfunction, and a quality of service QoS function and send an upstreamfirst user side physical layer frame to the OLT11 according to theupstream time slice through the ONU physical converter 12 or receive,according to the downstream time slice, a downstream first user sidephysical layer frame which is sent by the OLT11 through the ONU physicalconverter 12.

It should be noted that in an optical fiber network system, the PONphysical signal transmitted between the ONU physical converter and theOLT is specifically a PON optical signal, where the PON optical signalcorresponds to a PON physical layer frame (PON PHY).

In this embodiment, a non-PON optical fiber connection may at leastinclude a DSL (Digital Subscriber Line), a cable TV cable, an Ethernetnetwork cable, a power cable, or a wireless interface, where thewireless interface may be a Wi-Fi (Wireless Fidelity) interface.

Accordingly, the non-PON physical signal specifically includes a DSLsignal, a cable TV cable signal, an Ethernet signal, a power cablesignal, or a wireless signal.

The first user side physical layer frame includes a physical layer framecorresponding to the DSL, the cable TV cable signal, the Ethernetsignal, the power cable signal, or the wireless signal.

It should be noted that an existing optical fiber network includes: anEPON (Ethernet Passive Optical Network), a next generation EPON, a GPON(Gigabit Passive Optical Network), and a next generation GPON. In thisembodiment, for ease of descriptions, the EPON is taken as an example toillustrate how this invention makes improvements.

In addition, in this embodiment, as shown in FIG. 2, a customer premisesequipment can integrate an existing CPE to function as an integrateddevice, which can be explained specifically as follows. The customerpremises equipment 13 obtained through integration can be obtained byconnecting an existing CPE132 and a virtual ONU131, where the virtualONU is a module having the following functions. Connected to the ONUphysical converter 12 through the non-PON optical fiber and located onthe user side; and configured to realize the ONU control plane function,the PON MAC function, and the quality of service QoS function. Send theupstream first user side physical layer frame to the OLT11 according tothe upstream time slice through the ONU physical converter 12 orreceive, according to the downstream time slice, the downstream firstuser side physical layer frame which is sent by the OLT11 through theONU physical converter 12.

Specifically, the existing CPE132 inside the customer premises equipment13 can be connected to a UE (User Equipment); and the virtual ONU131 canchoose to connect to a CPE through the DSL, the cable TV cable signal,the Ethernet signal, the power cable signal, or the wireless interface.In this case, a second user side physical layer frame is correspondingto a DSL physical layer frame, a power cable physical layer frame, acable physical layer frame, an Ethernet physical layer frame, or awireless physical layer frame. For example, when the existing CPE132connects to the virtual ONU131 through the Ethernet network cable, thesecond user side physical layer frame is the Ethernet physical layerframe.

In this embodiment, the CPE may be a home gateway, an enterprise networkgateway, or a cell gateway; the UE may be a device such as a cell phone,a tablet computer, or a notebook computer.

Further, the access system for the optical fiber network provided in thepresent invention may include transmission in an upstream direction andin a downstream direction, where the upstream direction is from the CPEto the OLT while the downstream direction is from the OLT to the CPE.

Further, as shown in FIG. 3, the access system includes a POS,configured to receive the PON physical signal sent by the OLT, assignand send the PON physical signal to different ONU physical converters.

In the access system for the optical fiber network provided in thisembodiment, the customer premises equipment is established, and the ONUcontrol plane function, the PON MAC function, and the QoS function onthe existing ONU are moved downwards to the customer premises equipment.After the forgoing functions are removed from the existing ONU, theexisting ONU becomes the ONU physical converter and only has a functionof converting the PON physical layer frame and the first user sidephysical layer frame. Therefore, a carrier does not need to maintain theONU control plane function, PON MAC function, and QoS function, whichlowers maintenance complexity and greatly reduces maintenance costs.

Embodiment 2

Based on an access system for an optical fiber network provided inEmbodiment 1 and because the system provided in Embodiment 1 makes aninnovative improvement on an existing ONU, where a customer premisesequipment located on a user side is established, an ONU control planefunction, a PON MAC function, and a QoS function on the existing ONU aremoved downwards to the customer premises equipment. After the forgoingfunctions are removed from the existing ONU, the existing ONU becomes anONU physical converter and only has a function of converting the PONphysical layer frame and the first user side physical layer frame.Meantime, the access system provided in Embodiment 1 also makes animprovement on a protocol stack used for communication in the opticalfiber network. Therefore, the present invention also makes animprovement on a communication method for the optical fiber network.Embodiment 2 provides an improved communication method.

Embodiment 2 first describes an improved protocol stack used by theaccess system.

Embodiment 2 uses a connection of the customer premises equipment andthe ONU physical converter through a DSL as an example for description.FIG. 4 provides a schematic diagram of a protocol stack of a new accesssystem for the optical fiber network in a case where an Ethernet bridgeis not used.

In the protocol stack, a direction from a CPE to an OLT is an upstreamdirection, and a direction from the OLT to the CPE is a downstreamdirection; downstream data is transmitted in a TDM (Time-DivisionMultiplexing) manner while upstream data is transmitted in a TDMA (TimeDivision Multiple Access) manner.

The OLT is connected to the ONU physical converter through an opticalfiber and can implement DBA (Dynamic Bandwidth Allocation) for aconnected customer premises equipment to assign an upstream time sliceand a downstream time slice for the connected customer premisesequipment and send information which includes the upstream time sliceand the downstream time slice to the customer premises equipment. TheOLT is further configured to send a PON physical layer frame to the ONUphysical converter through the optical fiber after the OLT converts aPON MAC layer frame to the PON physical layer frame.

The upstream time slice is configured to indicate a moment when thecustomer premises equipment sends a first upstream user side physicallayer frame to the OLT. Upstream data is sent in the TDMA manner, whichcan prevent that the upstream data sent by different customer premisesequipment collides on a physical converter. The ONU physical converterdoes not need to perform QoS scheduling any more but performs only aphysical layer frame conversion, which can greatly reduce maintenancecosts. The downstream time slice is configured to instruct the customerpremises equipment to receive a first downstream user side physicallayer frame from the OLT.

The ONU physical converter is connected to a plurality of customerpremises equipment through DSLs and can complete conversion between thePON physical layer frame (PON PHY) and a DSL physical layer frame (DSLPHY).

The customer premises equipment can receive a user side interfacephysical layer frame (user side interface PHY) and convert the user sideinterface physical layer frame to the PON MAC layer frame throughcompletion of the PON MAC function of the customer premises equipment.After the customer premises equipment adds a DSL physical layer frameheader to the PON MAC layer frame, the customer premises equipmentobtains the DSL physical layer frame (DSL PHY) and sends the DSLphysical layer frame to the ONU physical converter through the DSL.

The CPE may be a home gateway, an enterprise network gateway, or a cellgateway and may be respectively used for different access scenarios suchas home access, enterprise access, or mobile transmission and access.

FIG. 5 provides a schematic diagram of the protocol stack of the newaccess system for the optical fiber network in a case where the Ethernetbridge is used, which is different from the protocol stack in FIG. 4.The Ethernet bridge is added in the protocol stack in FIG. 5 to realizedata forwarding through different interfaces of the Ethernet bridge. Forthe protocol stack in FIG. 5, a process for upstream and downstream datatransmission is as follows.

After receiving a downstream PON physical layer frame, the ONU physicalconverter terminates a PON physical layer, adds an Ethernet broadcastframe header to a downstream PON MAC layer frame, and sends thedownstream PON MAC layer frame with the Ethernet broadcast frame headerto a corresponding DSL physical layer processing unit through theEthernet bridge. The DSL physical layer processing unit removes theEthernet broadcast frame header from an Ethernet frame, encapsulates thePON MAC layer frame into the DSL physical layer frame, and sends the DSLphysical layer frame to the customer premises equipment.

Reversely, after receiving the downstream PON physical layer frame, theDSL physical layer processing unit terminates a DSL physical layer, andconverts the downstream PON physical layer frame to obtain thedownstream PON MAC layer frame. After the DSL physical layer processingunit generates the Ethernet frame by adding the Ethernet broadcast frameheader to the downstream PON MAC layer frame, the Ethernet frame isforcibly forwarded through the Ethernet bridge. After receiving theEthernet frame, a PON physical layer processing unit removes theEthernet broadcast frame header to obtain the PON MAC layer frame,encapsulates the PON MAC layer frame into the PON physical layer frame,and sends the PON physical layer frame to the OLT.

Besides, it should be noted that, in customer premises equipmentprovided in the present invention, each customer premises equipment hasits own ONU ID. In an EPON or a next generation EPON, throughmodification of a preamble in the Ethernet frame, the Ethernet frame cancarry the ONU ID to obtain an EPON MAC layer frame. Therefore, theprotocol stack shown in FIG. 5 is more proper for use in the EPON or thenext generation EPON.

Secondly, it should be noted in this embodiment that due to theimprovement of the protocol stack, a configuration method of the newaccess system for the optical fiber network is accordingly improved,which is specifically described as follows.

In the prior art, the CPE on the optical fiber network needs to beconfigured through TR069 (a CPE wide area network management protocol)by various parameters delivered by an automatic configuration server ona network side. Physical parameters of an access line between an ONU andthe user side equipment need to be statically configured and thendelivered to the user side equipment through the ONU. When the number ofONUs is huge, the maintenance is more difficult and costly.

For example, the connection between the ONU and the user side equipmentthrough the DSL is taken as an example for description. The ONU and theuser side equipment require the following physical parameters of a DSLaccess line: minimum data rate, maximum data rate, minimum data rate inlow power state, maximum interleaving delay, or actual interleavingdelay.

Meantime, in the prior art, the ONU needs to report various stateparameters of the access line to the OLT. For example, when the ONU isconnected to the user side equipment through the DSL, the ONU needs toreport various state parameters of the DSL access line to the OLT, suchas a DSL type, a DSL interface state (DSL Port State), actual upstreamand downstream data rate (Actual data rate Up- and Downstream), orattainable upstream and downstream data rate (Attainable data rate Up-and Downstream).

To solve a problem of high costs when a carrier maintains and configuresmassive ONUs in the prior art, this embodiment provides two improvedconfiguration methods.

First, FIG. 6 provides a schematic diagram of the access system for theoptical fiber network that requires no configuration of the ONU physicalconverter, which is described as follows.

In the access system for an optical fiber network shown in FIG. 6,connections between the customer premises equipment and the ONU physicalconverter respectively through the DSL, a cable TV cable, and a wirelessinterface are taken as examples. Corresponding deployment manners arerespectively FTTB (Fibre To The Building)/FTTN (Fibre To The Node), FTTC(Fibre To The Curb), and FTTDp (Fibre to Drop/Distribution Point).Moreover, a DSL modem, a cable modem (cable TV cable modem), and awireless terminal are integrated in the customer premises equipment. ADSLAM (DSL Access Multiplexer), a CMTS (Cable Modem Termination System),and a Wi-Fi AP (Access Point)/BS (Base Station) are integrated with theONU physical converter.

In the access system for the optical fiber network shown in FIG. 6, aconfiguration management manner of the ONU physical converter originallymaintained by the carrier is exchanged with a configuration managementmanner of the customer premises equipment on the user side.Configuration of physical parameters of the access line between the ONUand the user side equipment is transferred to the customer premisesequipment. The ONU physical converter requires no configuration of thephysical parameters and only needs to forward the physical parameters.Report of state parameters of the access line is also transferred to thecustomer premises equipment. The carrier does not need to maintainconfiguration management of the ONU physical converter. This greatlyreduces maintenance costs.

Moreover, the ONU physical converter can negotiate with the customerpremises equipment to obtain the physical parameters of the access line.The customer premises equipment rather than the ONU physical converterreports the state parameters of the access line to the OLT.

The physical parameters of the access line can be configured on thecustomer premises equipment through a PON management plane protocol. Allstate parameters of the access line can also be reported through the PONmanagement plane protocol.

For example, for a GPON or a next generation GPON, the customer premisesequipment supports an OMCI (ONT Management and Control Interface)protocol to configure and manage the customer premises equipment and toconfigure the physical parameters of the access line or report the stateparameters of the access line. For the EPON or the next generation EPON,the customer premises equipment supports an ETH OAM (ETH OperationAdministration and Maintenance) protocol to configure and manage thecustomer premises equipment, and to complete the configuration of thephysical parameters of the access line and the report of all the stateparameters of the access line.

Further, the customer premises equipment and the CPE can be integratedinto a device. Therefore, the physical parameters of the access line canalso be configured by using a configuration protocol (such as TR-069) ofthe CPE.

Second, FIG. 7 provides another schematic diagram of the access systemfor the optical fiber network that requires no configuration of the ONUphysical converter, which is described as follows.

Different from the first configuration manner, in the secondconfiguration manner, a physical layer of the customer premisesequipment and a physical layer of the ONU physical converter on bothsides of the access line are exchanged, namely, a physical layerprocessing function of a user side access line of the existing ONU ismoved downwards to the user side equipment (customer premises equipment)in front of the CPE, and the physical layer processing function of theaccess line of the user side equipment in front of the original CPE ismoved upwards to an access node ONU (ONU physical converter).

Specifically, in the access system for the optical fiber network shownin FIG. 7, the connections between the customer premises equipment andthe ONU physical converter respectively through the DSL, the cable TVcable, and the wireless interface are taken as examples. Correspondingdeployment manners are respectively FTTB/FTTN, FTTC, and FTTDp. The DSLmodem, the cable modem, and the wireless terminal are integrated in theONU physical converter. The DSLAM, the CMTS, and the Wi-Fi AP/BS areintegrated with the customer premises equipment.

In the second configuration manner, only physical layer chips of the ONUphysical converter and the user side equipment need to be exchanged. Forexample, if the customer premises equipment and the ONU physicalconverter are connected to each other through the DSL, the DSL Modemrather than the DSLAM is built in the ONU physical adapter. The customerpremises equipment has a DSL physical layer processing function (that isa DSLAM function of a single interface) of the existing ONU. The CPE inthe customer premises equipment is interconnected with the DSL Modemthrough the DSLAM of the single interface. The DSLAM of the singleinterface does not have an interface aggregation function but can bebuilt in the CPE. The ONU physical adapter can have a plurality of DSLModems and support a plurality of DSL interfaces.

Similarly, as shown in FIG. 7, if the customer premises equipment isconnected to the ONU physical converter by using the cable TV cable, theCable Modem rather than the CMTS is built in the ONU physical adapter.The customer premises equipment has a Cable physical layer processingfunction (that is a CMTS function of a single interface) of the originalONU. The CPE is interconnected with the Cable Modem through the CMTS ofthe single interface. Actually, the CMTS of the single interface doesnot have the interface aggregation function, and can also be built inthe CPE. The ONU physical adapter can have a plurality of Cable Modemsand support a plurality of cable TV cable interfaces.

Similarly, as shown in FIG. 7, if the customer premises equipment isconnected to the ONU physical converter by using wireless technology,the wireless terminal rather than the BS/AP is built in the ONU physicaladapter. The customer premises equipment has a wireless physical layerprocessing function (that is a BS/AP function) of the original ONU. TheCPE in the customer premises equipment is connected to the wirelessterminal through the BS/AP. Actually, the BS/AP supports access of onlyone wireless terminal of the ONU physical converter on the network sideand can also be built in the CPE. The ONU physical adapter can have aplurality of wireless terminals and support a plurality of customerpremises equipment.

In the second configuration manner provided in this embodiment, throughexchanging of the physical layer chips of the ONU physical converter andthe user side equipment (integrated with the customer premisesequipment), the configuration of the physical parameters of the accessline from the ONU to the user side equipment is transferred to thecustomer premises equipment. The ONU physical converter requires noconfiguration of the physical parameters and only needs to forward thephysical parameters. The report of the state parameters of the accessline is also transferred to the customer premises equipment. The carrierdoes not need to maintain configuration management of the ONU physicalconverter. This greatly reduces maintenance costs.

Furthermore, according to the improvement of the present invention onthe protocol stack and physical parameter configuration manner of theaccess system for the optical fiber network, the communication methodbased on the access system for the optical fiber network is provided. Asshown in FIG. 8, the communication method specifically includes thefollowing steps.

Step 201: Establish, by the customer premises equipment, a communicationconnection with the ONU physical converter according to a default firstphysical layer parameter, where the default first physical layerparameter is reserved on the customer premises equipment and the ONUphysical converter.

The connection between the customer premises equipment and the ONUphysical converter through the DSL is taken as an example fordescription. The first physical layer parameter may include thefollowing: minimum data rate, maximum data rate, minimum data rate inlow power state, maximum interleaving delay, or actual interleavingdelay.

Step 202: Establish, by the customer premises equipment, a communicationconnection with the OLT.

Step 203: Receive, by the customer premises equipment, a second physicallayer parameter delivered by the OLT, where the second physical layerparameter is a new physical layer parameter or an updated physical layerparameter delivered by the OLT.

Step 204: Negotiate, by the customer premises equipment, with the ONUphysical converter and establish a communication connection according tothe second physical layer parameter delivered by the OLT.

Step 205: Report, by the customer premises equipment, a data queue stateto the OLT.

Step 206: Assign, by the OLT, time slices to the customer premisesequipment.

The time slices include the upstream time slice and the downstream timeslice. After completing time slice assignment, the OLT sendsconfiguration information which includes the upstream time slice and thedownstream time slice to the customer premises equipment. The upstreamtime slice is used to indicate a moment when the customer premisesequipment sends upstream data to the OLT, and the downstream time sliceis used to indicate a moment when the customer premises equipmentreceives downstream data sent by the OLT.

Step 207: Exchange, by the customer premises equipment, data with theOLT according to the time slices.

Further, after the establishing a communication connection between thecustomer premises equipment and the OLT in step 207, the method mayinclude the following.

Reporting, by the customer premises equipment, a physical line state ofthe communication connection with the OLT to the OLT.

Further, after completing the establishment of the communicationconnection, this embodiment further provides a method for adjustingbandwidth online. As shown in FIG. 9, the method specifically includesthe following steps.

Step 301: Receive, by the OLT, a request to increase bandwidth fortemporary communication of a user, where the request to increase thebandwidth for the temporary communication may be temporarily sent by theuser or reserved for the user in advance. After the reserved time isreached, the request is sent by a carrier network side to the OLT or isactively sent by the carrier to the OLT or the like.

Step 302: Reassign, by the OLT, bandwidth to the customer premisesequipment, and obtain a third physical layer parameter according tocurrent bandwidth assignment.

Step 303: Deliver, by the OLT, the third physical layer parameter to thecustomer premises equipment.

Step 304: Establish, by the customer premises equipment, a newcommunication connection with the ONU physical converter according tothe third physical layer parameter.

Step 305: Obtain, by the customer premises equipment, the reassignedbandwidth and use the reassigned bandwidth to communicate with the OLT.

Step 306: Restore, by the OLT, bandwidth for the customer premisesequipment after the temporary communication ends, where the restoring,by the OLT, bandwidth for the customer premises equipment specificallyincludes the following steps.

Step 306-1: Deliver, by the OLT, the second physical layer parameter tothe customer premises equipment.

Step 306-2: Re-establish, by the customer premises equipment, a newcommunication connection with the ONU physical converter according tothe second physical layer parameter.

Step 306-3: Re-establish, by the customer premises equipment, acommunication connection with the OLT to restore the bandwidth beforethe temporary communication for the customer premises equipment.

This embodiment provides the communication method based on the accesssystem of the optical fiber network in Embodiment 1. In this method, thecustomer premises equipment establishes the communication connectionwith the OLT through the physical layer parameters which is delivered bythe OLT to the customer premises equipment, and the ONU physicalconverter maintained by the carrier side requires no configuration,which saves maintenance costs of the carrier. The customer premisesequipment directly reports the physical line state to the OLT withoutparticipation of the ONU physical converter. The customer premisesequipment sends and receives data according to the upstream time sliceand the downstream time slice; therefore, no data collision occurs. ThePON control plane of the ONU physical converter does not need to bemaintained, which also saves maintenance costs of the carrier.

Embodiment 3

This embodiment provides a customer premises equipment, where thecustomer premises equipment is connected to an ONU physical converterthrough a non-PON optical fiber and is located on a user side, and isconfigured to realize an ONU control plane function and a PON MACfunction, send a first user side physical layer frame to the OLT throughthe ONU physical converter according to an upstream time slice assignedby an OLT, or receive, according to a downstream time slice assigned bythe OLT, a first user side physical layer frame which is sent by the OLTthrough the ONU physical converter.

Further, the customer premises equipment is configured to receive asecond physical layer parameter which is delivered by the OLT throughthe ONU physical converter and establish a new communication connectionwith the ONU physical converter according to the second physical layerparameter delivered by the OLT.

The customer premises equipment is further configured to the following.Before receiving the second physical layer parameter which is deliveredby the OLT through the ONU physical converter, establish a communicationconnection with the ONU physical converter according to a default firstphysical layer parameter and establish a communication connection withthe OLT. The default first physical layer parameter is reserved on thecustomer premises equipment.

Further, the customer premises equipment is configured to report aphysical line state of the communication connection with the OLT to theOLT through the ONU physical converter.

Further, as shown in FIG. 10, the customer premises equipmentspecifically includes the following units. A user side interface unit301 is configured to receive an upstream second user side physical layerframe sent by a user or send a downstream second user side physicallayer frame to the user. A virtual ONU processing unit 302 is configuredto realize the ONU control plane function, the PON MAC function, and aquality of service QoS function, encapsulate the upstream second userside physical layer frame into an upstream PON MAC layer frame, send theupstream PON MAC layer frame to the ONU physical converter through auser side physical layer processing unit 303 according to the upstreamtime slice assigned by the OLT or receive, according to the downstreamtime slice assigned by the OLT, a downstream PON MAC layer frame sent bythe user side physical layer processing unit 303, convert the downstreamPON MAC layer frame to the downstream second user side physical layerframe, and send the downstream second user side physical layer frame tothe user side physical layer processing unit 303 through the user sideinterface unit 301.

It should be noted that the ONU control plane function includes thefollowing. Working with the OLT to complete ranging of the customerpremises equipment so that the OLT can assign the upstream time sliceand the downstream time slice to the customer premises equipmentaccording the ranging result, and optionally supporting the receiving ofconfiguration of physical parameters of an access line and the report ofall state parameters of the access line.

The PON MAC function includes: completing framing of the PON MAC layerframe.

The QoS function includes: establishing a queue and an assignmentpriority of upstream data for the customer premises equipment. The userside physical layer processing unit 303, configured to convert theupstream PON MAC layer frame sent by the virtual ONU processing unit 302to an upstream first user side physical layer frame corresponding to anon-PON physical signal and send the upstream first user side physicallayer frame to the ONU physical converter through the non-PON physicalsignal; or receive a downstream first user side physical layer framesent by the ONU physical converter, convert the downstream first userside physical layer frame to the downstream PON MAC layer frame, andsend the downstream PON MAC layer frame to the virtual ONU processingunit 302.

Further, as shown in FIG. 11, the customer premises equipment alsoincludes a CPE unit 304, where the CPE unit 304 is connected to the userside interface unit 301 and a user equipment UE and is configured toreceive the downstream second user side physical layer frame sent by theuser side interface unit 301 and forward the downstream second user sidephysical layer frame to the UE, or receive upstream data sent by the UE,convert the upstream data to an upstream second user side physical layerframe, and send the upstream second user side physical layer frame tothe user side interface unit 301.

Further, as shown in FIG. 12, the customer premises equipment includesan external power supply unit 305, which is configured to provide powerfor the ONU physical converter.

This embodiment provides the customer premises equipment, where the ONUcontrol plane function, the PON MAC function, and the QoS function on anexisting ONU are moved downwards to the customer premises equipment.After the forgoing function modules are removed from the existing ONU,the existing ONU becomes the ONU physical converter and only has afunction of converting the PON physical layer frame and the first userside physical layer frame conversion function. Therefore, a carrier doesnot need to maintain the ONU control plane function, the PON MACfunction, and the QoS function, which lowers maintenance complexity andgreatly reduces maintenance costs.

Embodiment 4

This embodiment provides an ONU physical converter, where the ONUphysical converter is connected to an OLT through an optical fiber andis configured to receive a PON physical layer frame which is sent by theOLT through a PON physical signal, convert the PON physical layer frameto a first user side physical layer frame corresponding to a non-PONphysical signal, and send the first user side physical layer frame to acustomer premises equipment through the non-PON physical signal; orreceive a first user side physical layer frame which is sent by thecustomer premises equipment through the non-PON physical signal, convertthe first user side physical layer frame to a PON physical layer framecorresponding to the PON physical signal, and send the PON physicallayer frame to the OLT through the PON physical signal.

Further, the ONU physical converter is further configured to forward tothe customer premises equipment a second physical layer parameterdelivered by the OLT and establish a new communication connection withthe customer premises equipment according to the second physical layerparameter delivered by the OLT.

Further, the ONU physical converter is further configured to establish acommunication connection with the customer premises equipment accordingto a default first physical layer parameter before the customer premisesequipment receives the second physical layer parameter which isforwarded by the OLT through the ONU physical converter. The defaultfirst physical layer parameter is reserved on the customer premisesequipment.

Further, the ONU physical converter is further configured to forward tothe OLT a physical line state of the communication connection reportedby the customer premises equipment.

It should be noted that this embodiment provides two manners for the ONUphysical converter to convert data, and in the first manner, aconversion manner of an upstream direction and a conversion manner of adownstream direction are included, which is specifically described asfollows.

In the first manner:

1. Description of the Upstream Direction

As shown in FIG. 13, the ONU physical converter includes: a non-PONphysical layer processing unit 401, a switch control unit 402, a switchunit 403, and a PON physical layer processing unit 404. The non-PONphysical layer processing unit 401 is configured to receive an upstreamfirst user side physical layer frame which is sent by the customerpremises equipment through the non-PON physical signal and convert theupstream first user side physical layer frame to an upstream PON MAClayer frame.

The switch control unit 402 is configured to generate a switch controlsignal corresponding to the customer premises equipment when receivingthe upstream PON MAC layer frame sent by the customer premises equipmentand send the switch control signal corresponding to the customerpremises equipment to the switch unit 403.

The switch unit 403, including one output interface 0 and at least oneinput interface 1-n, where there is one-to-one correspondence betweenthe input interface 1-n and the customer premises equipment connected tothe ONU physical converter, is configured to connect, according to theswitch control signal corresponding to the customer premises equipment,a channel between an input interface corresponding to the customerpremises equipment and an output interface. The channel is configuredfor the non-PON physical layer processing unit 401 to send the upstreamPON MAC layer frame obtained through conversion by the non-PON physicallayer processing unit 401 to the PON physical layer processing unit 404.The PON physical layer processing unit 404 is configured to convert theupstream PON MAC layer frame to an upstream PON physical layer frame andsend the upstream PON physical layer frame to the OLT through the PONphysical signal.

The following describes data conversion in the upstream direction withexamples.

As shown in FIG. 14, an architecture diagram of an access system for anoptical fiber network is provided to realize upstream communications.The system includes the OLT, a plurality of ONU physical convertersconnected to the OLT through optical fibers, and a plurality of customerpremises equipment connected to the ONU physical converter. The accesssystem is applicable to a situation that a small number of customerpremises equipment are connected to each ONU physical converter.

In this embodiment, connections between the customer premises equipmentand the ONU physical converter through a DSL, a power cable, a cable TVcable, an Ethernet network cable, and a wireless interface are taken asexamples for description. Accordingly, a non-PON physical layerprocessing unit in this embodiment can be specifically a DSL physicallayer processing unit, a power cable physical layer processing unit, acable physical layer processing unit, an Ethernet physical layerprocessing unit, and a wireless physical layer processing unit.

Accordingly, the upstream first user side physical layer frame can berespectively an upstream first DSL physical layer frame, an upstreamfirst power cable physical layer frame, an upstream first cable physicallayer frame, an upstream first Ethernet physical layer frame, and anupstream first wireless physical layer frame.

For example, as shown in FIG. 14, a customer premises equipment_11 isconnected to an ONU physical converter_1 through the DSL, and then thenon-PON physical layer processing unit corresponding to the customerpremises equipment_11 is specifically the DSL physical layer processingunit. A customer premises equipment_1N is connected to the ONU physicalconverter_1 through the power cable, and then the non-PON physical layerprocessing unit corresponding to the customer premises equipment_1N isspecifically the power cable physical layer processing unit. A customerpremises equipment_N1 is connected to an ONU physical converter_Nthrough the cable TV cable, and then the non-PON physical layerprocessing unit corresponding to the customer premises equipment_N1 isspecifically the cable physical layer processing unit. A customerpremises equipment_NN is connected to the ONU physical converter_Nthrough the wireless interface, and then the non-PON physical layerprocessing unit corresponding to the customer premises equipment_NN isspecifically the wireless physical layer processing unit.

For FIG. 14, further, the customer premises equipment can also beconnected to the ONU physical converter through the Ethernet networkcable, and then the non-PON physical layer processing unit correspondingto the customer premises equipment is specifically the Ethernet physicallayer processing unit.

Specifically, the non-PON physical layer processing unit converts theupstream first user side physical layer frame to the upstream PON MAClayer frame, which can be as follows. The non-PON physical layerprocessing unit removes an upstream first user side physical layer frameheader from the upstream first user side physical layer frame andobtains the upstream PON MAC layer frame.

The connection between the customer premises equipment and the ONUphysical converter through the DSL is used as an example fordescription. The DSL physical layer processing unit converts theupstream first DSL physical layer frame to the upstream PON MAC layerframe. The DSL physical layer processing unit removes a DSL physicallayer frame header from the upstream first DSL physical layer frame andobtains the upstream PON MAC layer frame.

The PON physical layer processing unit is configured to convert theupstream PON MAC layer frame to the upstream PON physical layer frameand send the upstream PON physical layer frame to the OLT through thePON physical signal.

The switch control unit is configured to generate the switch controlsignal corresponding to the customer premises equipment when receivingthe upstream PON physical layer frame sent by the customer premisesequipment and send the switch control signal corresponding to thecustomer premises equipment to the switch unit. The switch unit includesone output interface and at least one input interface, and there isone-to-one correspondence between the input interface and the customerpremises equipment connected to the ONU physical converter. For example,in Embodiment 1, an interface 0 is the output interface, and aninterface 1 to an interface n are input interfaces.

The forgoing switch control signal is used to instruct the switch unitto connect the input interface corresponding to the switch controlsignal and the output interface to form a channel.

A powered unit is configured to obtain electrical energy from theexternal power supply unit in the customer premises equipment to realizeobtaining power from a user side, which can solve the problem ofdifficulties in long-distance power supply for the ONU for a carrier.

It should be further noted that when the customer premises equipment isconnected to the ONU physical converter through the power cable, powercan be supplied directly through the power cable.

The switch unit is configured to connect, according to the switchcontrol signal, the channel between an input interface corresponding tothe customer premises equipment and an output interface, where thechannel is configured to send the upstream PON MAC layer frame obtainedthrough conversion by the non-PON physical layer processing unitcorresponding to the customer premises equipment to the PON physicallayer processing unit.

For example, as shown in FIG. 14, when the customer premisesequipment_1N sends a first upstream user side physical layer frame tothe OLT, the power cable physical layer processing unit notifies theswitch control unit, the switch control unit sends the switch controlsignal to the switch unit, and the switch unit connects the interface nand the interface 0 to form a channel after the switch unit receives theswitch control signal. The customer premises equipment can then send theupstream PON physical layer frame to the OLT through the power cablephysical layer processing unit.

The ONU physical converter may also include a PON optical module, wherethe PON optical module is located in an upstream direction of the PONphysical layer processing unit, and the ONU physical converter sends thePON physical signal to the OLT through the PON optical module.Accordingly, the switch control signal can further be configured tocontrol whether the PON optical module glows or not.

FIG. 15 is a schematic diagram of correspondence between user sideinterfaces and the switch control signal and PON optical module stateprovided by this embodiment. The customer premises equipment sends thefirst upstream user side physical layer frame to the OLT according to anupstream time slice assigned by the OLT.

2. Description of the Downstream Direction.

The following describes data conversion in the downstream direction withexamples.

Further, as shown in FIG. 16, the ONU physical converter includes thefollowing. A PON physical layer processing unit 404, a non-PON physicallayer processing unit 401, and interfaces 1-n respectively correspondingto customer premises equipments connected to the ONU physical converter,and a downstream data replicating unit 406. The PON physical layerprocessing unit 404 is configured to receive a downstream PON physicallayer frame sent by the OLT through the PON physical signal and convertthe downstream PON physical layer frame to a downstream PON MAC layerframe.

Interfaces 1-n are configured respectively to connect lines between thedownstream data replicating unit 406 and the non-PON physical layerprocessing unit 401, where the lines are configured to send thedownstream PON MAC layer frame obtained through conversion by the PONphysical layer processing unit 404 to the non-PON physical layerprocessing unit 401.

The downstream data replicating unit 406 is configured to replicate thedownstream PON MAC layer frame obtained through conversion by the PONphysical layer processing unit 404 to all lines which belong to the ONUphysical converter.

The non-PON physical layer processing unit 401 is configured to convertthe downstream PON MAC layer frame to the downstream first user sidephysical layer frame and send the downstream first user side physicallayer frame to the customer premises equipment through the non-PONphysical signal.

The following describes data conversion in the upstream direction withexamples.

As shown in FIG. 17, an architecture diagram of the access system forthe optical fiber network is provided to realize downstreamcommunications. The system includes the OLT, a plurality of ONU physicalconverters connected to the OLT through optical fibers, and a pluralityof customer premises equipments connected to the ONU physical converter.The access system is applicable to a situation that a small number ofcustomer premises equipments are connected to each ONU physicalconverter.

The following provides specific descriptions.

The ONU physical converter specifically includes a PON physical layerprocessing unit, a non-PON physical layer processing unit, andinterfaces respectively corresponding to customer premises equipmentsconnected to the ONU physical converter, and a downstream datareplicating unit. The PON physical layer processing unit is configuredto receive the downstream PON physical layer frame which is sent by theOLT through the PON physical signal and convert the downstream PONphysical layer frame to the downstream PON MAC layer frame. The non-PONphysical layer processing unit is configured to convert the downstreamPON MAC layer frame to a downstream first user side physical layer framecorresponding to the non-PON physical signal and send the downstreamfirst user side physical layer frame to the customer premises equipmentthrough the non-PON physical signal.

Similar to the foregoing description, in this embodiment, connectionsbetween the customer premises equipment and the ONU physical converterthrough the DSL, the power cable, the cable TV cable, the Ethernetnetwork cable, and the wireless interface are taken as examples fordescription. Accordingly, the non-PON physical layer processing unit inthis embodiment is specifically the DSL physical layer processing unit,the power cable physical layer processing unit, the cable physical layerprocessing unit, the Ethernet physical layer processing unit, and thewireless physical layer processing unit.

Accordingly, the downstream first user side physical layer frame isrespectively a downstream first DSL physical layer frame, a downstreamfirst power cable physical layer frame, a downstream first cablephysical layer frame, and a downstream first wireless physical layerframe.

For example, as shown FIG. 17, a customer premises equipment_11 isconnected to an ONU physical converter_1 through the DSL, and then thenon-PON physical layer processing unit corresponding to the customerpremises equipment_11 is specifically the DSL physical layer processingunit. A customer premises equipment_1N is connected to the ONU physicalconverter_1 through the power cable, and then the non-PON physical layerprocessing unit corresponding to the customer premises equipment_1N isspecifically the power cable physical layer processing unit. A customerpremises equipment_N1 is connected to an ONU physical converter_Nthrough the cable TV cable, and then the non-PON physical layerprocessing unit corresponding to the customer premises equipment_N1 isspecifically the cable physical layer processing unit. A customerpremises equipment_NN is connected to the ONU physical converter_Nthrough the wireless interface, and then the non-PON physical layerprocessing unit corresponding to the customer premises equipment_NN isspecifically the wireless physical layer processing unit.

Further, for FIG. 17, the customer premises equipment can also beconnected to the ONU physical converter through the Ethernet networkcable, and then the non-PON physical layer processing unit correspondingto the customer premises equipment is specifically the Ethernet physicallayer processing unit.

The non-PON physical layer processing unit converts the downstream PONMAC layer frame to the downstream first user side physical layer frame,which can be specifically as follows. The non-PON physical layerprocessing unit adds a downstream first user side physical layer frameheader to the downstream PON MAC layer frame and obtains the downstreamfirst user side physical layer frame.

The connection between the customer premises equipment and the ONUphysical converter through the DSL is taken as an example fordescription. The DSL physical layer processing unit adds a downstreamfirst DSL physical layer frame header to the downstream first PON MAClayer frame and obtains the downstream first DSL physical layer frame.

The interfaces are configured respectively to connect the lines betweenthe downstream data replicating unit and the non-PON physical layerprocessing unit, where the lines are configured for the PON physicallayer processing unit to send the downstream PON MAC layer frameobtained through conversion by the PON physical layer processing unit tothe non-PON physical layer processing unit.

The downstream data replicating unit is configured to replicate thedownstream PON MAC layer frame obtained through conversion by the PONphysical layer processing unit to all lines which belong to the ONUphysical converter.

Further, during the downstream sending process shown in FIG. 17, the PONphysical layer processing unit can convert the downstream PON MAC layerframe to an Ethernet frame and send the Ethernet frame to each interfacethrough the downstream data replicating unit. For example, this mannercan be used in a scenario where an Ethernet backplane is installed onthe ONU physical converter. The following specifically explainsfunctions of each component of the ONU physical converter in thisdownstream sending manner.

The PON physical layer processing unit is configured to receive thedownstream PON physical layer frame sent by the OLT, convert thedownstream PON physical layer frame to the downstream PON MAC layerframe, add an Ethernet broadcast frame header to the downstream PON MAClayer frame to obtain the downstream Ethernet frame, and send thedownstream Ethernet frame to the downstream data replicating unit.

The downstream data replicating unit is configured to replicate thedownstream Ethernet frame obtained through conversion by the PONphysical layer processing unit to all lines which belong to the ONUphysical converter and send the downstream Ethernet frame to the non-PONphysical layer processing unit through each interface.

The non-PON physical layer processing unit is configured to receive theforegoing Ethernet frame, remove the Ethernet broadcast frame headerfrom the Ethernet frame to obtain the downstream PON MAC layer frame,convert the downstream PON MAC layer frame to the downstream first userside physical layer frame, and send the downstream first user sidephysical layer frame to the customer premises equipment.

The second manner will now be described.

As shown in FIG. 18, the foregoing ONU physical converter includes: anon-PON physical layer processing unit 401, an Ethernet bridge 405, anda PON physical layer processing unit 404. The non-PON physical layerprocessing unit 401 is configured to receive the upstream first userside physical layer frame which is sent by the customer premisesequipment through the non-PON physical signal, convert the upstreamfirst user side physical layer frame to the upstream PON MAC layerframe, and send the upstream PON MAC layer frame to an Ethernet bridgethrough the input interface corresponding to the non-PON physical layerprocessing unit 401.

The Ethernet bridge 405, including one output interface 0 and at leastone input interface 1-n, is configured to receive the upstream PON MAClayer frame which is sent by the non-PON physical layer processing unitthrough the input interface 1-n and send the upstream PON MAC layerframe to the PON physical layer processing unit through the outputinterface 0.

The PON physical layer processing unit 404 is configured to receive theupstream PON MAC layer frame which is sent by the Ethernet bridge 405through the output interface 0, convert the upstream PON MAC layer frameto the upstream PON physical layer frame, and send the PON physicallayer frame to the OLT through the PON physical signal. The PON physicallayer processing unit 404 is configured to receive the downstream PONphysical layer frame sent by the OLT, convert the downstream PONphysical layer frame to the downstream PON MAC layer frame, add theEthernet broadcast frame header to the downstream PON MAC layer frame toobtain the Ethernet frame, and send the Ethernet frame to the Ethernetbridge 405.

The Ethernet bridge 405, including one input interface 0 and at leastone output interface 1-n, is configured to receive the Ethernet framewhich is sent by the non-PON physical layer processing unit 401 throughthe input interface 0 and send the Ethernet frame to the PON physicallayer processing unit through the output interface 1-n.

The non-PON physical layer processing unit 401 is specificallyconfigured to receive the Ethernet frame which is sent by the Ethernetbridge 405 through the output interface, remove the Ethernet broadcastframe header from the Ethernet frame to obtain the downstream PON MAClayer frame, convert the downstream PON MAC layer frame to thedownstream first user side physical layer frame, and send the downstreamfirst user side physical layer frame to the customer premises equipmentthrough the non-PON physical signal.

The following describes the second manner with an example.

As shown in FIG. 19, this embodiment further provides another accesssystem for the optical fiber network. When the number of interfacessupported by the ONU physical converter exceeds a certain number, theEthernet bridge is used on the ONU physical converter to support asituation where more interfaces exist (that is, there is a large numberof accessed customer premises equipments), which has low costs.

The access system shown in FIG. 19 specifically includes the OLT, aplurality of ONU physical converters connected to the OLT throughoptical fibers, and a plurality of customer premises equipmentsconnected to the ONU physical converter.

The following provides specific descriptions.

The ONU physical converter specifically includes the non-PON physicallayer processing unit, the PON physical layer processing unit, theEthernet bridge, and the powered unit, where the Ethernet bridgeincludes one output interface and at least one input interface.

The non-PON physical layer processing unit is configured to receive theupstream first user side physical layer frame which is sent by thecustomer premises equipment through the non-PON physical signal, convertthe upstream first user side physical layer frame to the upstream PONMAC layer frame, and send the upstream PON MAC layer frame to theEthernet bridge through the input interface corresponding to the non-PONphysical layer processing unit. It receives the downstream PON MAC layerframe which is sent by the Ethernet bridge through the output interface,convert the downstream PON MAC layer frame to the first downstream userside physical layer frame, and send the downstream first user sidephysical layer frame to the customer premises equipment through thenon-PON physical signal.

The PON physical layer processing unit is configured to receive theupstream PON MAC layer frame sent by the Ethernet bridge through theoutput interface, convert the upstream PON MAC layer frame to theupstream PON physical layer frame, send the upstream PON physical layerframe to the OLT through the PON physical signal. It receives thedownstream PON physical layer frame which is sent by the OLT through thePON physical signal, convert the downstream PON physical layer frame tothe downstream PON MAC layer frame, and send the downstream PON MAClayer frame to the corresponding non-PON physical layer processing unitthrough the output interface of the Ethernet bridge.

The Ethernet bridge is configured to receive the downstream PON MAClayer frame which is sent by the PON physical layer processing unitthrough the input interface, send the downstream PON MAC layer frame tothe non-PON physical layer processing unit through the output interface,or receive the upstream PON MAC layer frame which is sent by the non-PONphysical layer processing unit through the input interface and send theupstream PON MAC layer frame to the PON physical layer processing unitthrough the output interface.

The foregoing PON MAC layer frame in the downstream PON MAC layer frameor the upstream PON MAC layer frame needs to be an Ethernet frame, whichis more applicable to an EPON or a next generation EPON in this case.

The Ethernet bridge is configured to perform forced MAC forwarding(Forced MAC forwarding) in the upstream direction on the PON MAC layerframe from the user side interface, that is to forcibly forward the PONMAC layer frame to the upstream output interface leading to the OLT butnot to broadcast the PON MAC layer frame to the user side interface.Optionally, ARP (Address Resolution Protocol) proxy is realized on theEthernet bridge unit to return a MAC address of the ONU physical adapterto the user side equipment when receiving an ARP request from the userside.

In the downstream direction, the PON MAC layer frame from a PONinterface is forwarded according to the MAC address.

Further, as shown in FIG. 19, when data is transmitted in the upstreamdirection, the interface 1 to the interface n of the Ethernet bridge areinput interfaces and the interface 0 is the output interface. When datais transmitted in the downstream direction, the interface 1 to theinterface n of the Ethernet bridge are output interfaces, and theinterface 0 is the input interface.

The powered unit is configured to obtain electrical energy from theexternal power supply unit in the customer premises equipment to realizeobtaining power from the user side, which can solve the problem ofdifficulties in long-distance power supply for the ONU for the carrier.

It should be further noted that when the customer premises equipment isconnected to the ONU physical converter through the power cable, powercan be supplied directly through the power cable.

In this embodiment, connections between the customer premises equipmentand the ONU physical converter through the DSL, the power cable, thecable TV cable, the Ethernet cable, and the wireless interface are takenas examples for description. Accordingly, the non-PON physical layerprocessing unit in this embodiment is specifically the DSL physicallayer processing unit, the power cable physical layer processing unit,the cable physical layer processing unit, the Ethernet physical layerprocessing unit, and the wireless physical layer processing unit.

Accordingly, the foregoing first user side physical layer frame can berespectively the first DSL physical layer frame, the first power cablephysical layer frame, the first cable physical layer frame, the firstEthernet physical layer frame, and the first wireless physical layerframe.

For example, as shown FIG. 19, a customer premises equipment_11 isconnected to an ONU physical converter_1 through the DSL, and then thenon-PON physical layer processing unit corresponding to the customerpremises equipment_11 is specifically the DSL physical layer processingunit. A customer premises equipment_1N is connected to the ONU physicalconverter_1 through the power cable, and then the non-PON physical layerprocessing unit corresponding to the customer premises equipment_1N isspecifically the power cable physical layer processing unit. A customerpremises equipment_N1 is connected to an ONU physical converter_Nthrough the cable TV cable, and then the non-PON physical layerprocessing unit corresponding to the customer premises equipment_N1 isspecifically the cable physical layer processing unit. A customerpremises equipment_NN is connected to the ONU physical converter_Nthrough the wireless interface, and then the non-PON physical layerprocessing unit corresponding to the customer premises equipment_NN isspecifically the wireless physical layer processing unit.

For FIG. 19, further, the customer premises equipment can also beconnected to the ONU physical converter through the Ethernet networkcable, and then the non-PON physical layer processing unit correspondingto the customer premises equipment is specifically the Ethernet physicallayer processing unit.

Specifically, the non-PON physical layer processing unit converts theupstream first user side physical layer frame to the upstream PON MAClayer frame, which may be the following. The non-PON physical layerprocessing unit removes the upstream first user side physical layerframe header of the upstream first user side physical layer frame andobtains the upstream PON MAC layer frame.

The connection between the customer premises equipment and the ONUphysical converter through the DSL is taken as an example fordescription. The DSL physical layer processing unit converts theupstream first DSL physical layer frame to the upstream PON MAC layerframe, which is specifically. The DSL physical layer processing unitremoves the upstream first DSL physical layer frame header from theupstream first DSL physical layer frame and obtains the upstream PON MAClayer frame.

Specifically, the non-PON physical layer processing unit converts thedownstream PON MAC layer frame to the downstream first user sidephysical layer frame, which may be specifically as follows. The non-PONphysical layer processing unit adds a downstream first user sidephysical layer frame header to the downstream PON MAC layer frame andobtains the downstream first user side physical layer frame.

The connection between the customer premises equipment and the ONUphysical converter through the DSL is taken as an example fordescription. The DSL physical layer processing unit adds a downstreamDSL physical layer frame header to the downstream PON MAC layer frameand obtains the downstream DSL physical layer frame.

This embodiment provides the ONU physical converter, where the ONUcontrol plane function, the PON MAC function, and the QoS function on anexisting ONU are moved downwards to the customer premises equipment. TheONU physical converter is formed after the forgoing function modules areremoved from the existing ONU and only has a function of converting thePON physical layer frame and the first user side physical layer frame.Therefore, a carrier does not need to maintain the ONU control planefunction, the PON MAC function, and the QoS function, which lowersmaintenance complexity and greatly reduces maintenance costs.

A person of ordinary skill in the art may understand that all or a partof the steps of the foregoing embodiments may be implemented throughhardware, or may be implemented by a program instructing relevanthardware. The program may be stored in a computer readable storagemedium. The storage medium may be a read-only memory, a magnetic disk,or an optical disk or the like.

The foregoing descriptions are merely exemplary embodiments of thepresent invention, but are not intended to limit the present invention.Any modification, equivalent replacement, or improvement derived withinthe spirit and principle of the present invention shall fall within theprotection scope of the present invention.

What is claimed is:
 1. An access system for an optical fiber network,the access system comprising: an optical line terminal (OLT); an opticalnetwork unit (ONU) connected to the OLT through an optical fiber; and acustomer premises equipment connected to the ONU through a non-opticalconnection, the customer premises equipment being located on a userside; wherein the OLT is configured to assign an upstream time slice anda downstream time slice for the customer premises equipment; wherein theONU is configured to: receive a PON (Passive Optical Network) physicallayer frame which is sent by the OLT through a PON physical signal, toconvert the PON physical layer frame to a first user side physical layerframe corresponding to a non-optical physical signal, and to send thefirst user side physical layer frame to the customer premises equipmentthrough the non-optical physical signal; or receive a first user sidephysical layer frame which is sent by the customer premises equipmentthrough the non-optical physical signal, to convert the first user sidephysical layer frame to a PON physical layer frame corresponding to aPON physical signal, and send the PON physical layer frame to the OLTthrough the PON physical signal; and wherein the customer premisesequipment comprises: a user side interface, configured to receive anupstream second user side physical layer frame sent by a user, or send adownstream second user side physical layer frame to the user; a virtualONU processor, configured to realize a ONU control plane function and aPON MAC function, to encapsulate the upstream second user side physicallayer frame into an upstream PON MAC layer frame, to send the upstreamPON MAC layer frame to the ONU through a user side physical layerprocessor according to the upstream time slice assigned by the OLT orreceive, according to the downstream time slice assigned by the OLT, adownstream PON MAC layer frame sent by the user side physical layerprocessor, to convert the downstream PON MAC layer frame to thedownstream second user side physical layer frame, and to send thedownstream second user side physical layer frame to the user sidephysical layer processor through the user side interface; and the userside physical layer processor, configured to convert the upstream PONMAC layer frame sent by the virtual ONU processor to an upstream firstuser side physical layer frame corresponding to a non-optical physicalsignal and to send the upstream first user side physical layer frame tothe ONU through the non-optical physical signal, or to receive adownstream first user side physical layer frame sent by the ONU, toconvert the downstream first user side physical layer frame to thedownstream PON MAC layer frame, and to send the downstream PON MAC layerframe to the virtual ONU processor.
 2. A method using the systemaccording to claim 1, the method comprising: reporting, by the customerpremises equipment, a data queue state to the OLT through the ONU;assigning, by the OLT, an upstream time slice and a downstream timeslice to the customer premises equipment; sending configurationinformation which comprises the upstream time slice and the downstreamtime slice to the customer premises equipment through the ONU; andsending, by the customer premises equipment, according to theconfiguration information, upstream data to the OLT through the ONU orreceiving downstream data from the OLT.
 3. The method according to claim2, wherein before the customer premises equipment reports the data queuestate to an OLT through an ONU, the method further comprises: receiving,by the customer premises equipment, a second physical layer parameterwhich is delivered by the OLT through the ONU; and establishing, by thecustomer premises equipment, a new communication connection with the ONUaccording to the second physical layer parameter delivered by the OLT.4. The method according to claim 3, wherein before the customer premisesequipment receives the second physical layer parameter, the methodfurther comprises: establishing, by the customer premises equipment, acommunication connection with the ONU according to a default firstphysical layer parameter; and establishing, by the customer premisesequipment, a communication connection with the OLT, wherein the defaultfirst physical layer parameter is reserved on the customer premisesequipment and the ONU.
 5. The method according to claim 3, wherein afterthe customer premises equipment sends the upstream data to the OLTthrough the ONU or receives downstream data from the OLT, the methodfurther comprises: receiving, by the OLT, a request to increasebandwidth for temporary communication of a user, reassigning bandwidthto the customer premises equipment; delivering, by the OLT, a thirdphysical layer parameter to the customer premises equipment through theONU according to current bandwidth assignment; establishing, by thecustomer premises equipment, a new communication connection with the ONUaccording to the third physical layer parameter; obtaining, by thecustomer premises equipment, the reassigned bandwidth; delivering, bythe OLT, the second physical layer parameter to the customer premisesequipment through the ONU when the temporary communication ends;re-establishing, by the customer premises equipment, a communicationconnection with the ONU according to the second physical layerparameter; and re-establishing, by the customer premises equipment, acommunication connection with the ONU, so that the customer premisesequipment restores the bandwidth before the temporary communication. 6.A customer premises equipment, wherein the customer premises equipmentis connected to an optical network unit (ONU) through a non-opticalconnection and is located on a user side, and wherein the customerpremises equipment is configured to realize an ONU control planefunction and a passive optical network (PON) media access control (MAC)function, to send a first user side physical layer frame to an opticalline terminal (OLT) through the ONU according to an upstream time sliceassigned by the OLT or to receive a first user side physical layer framewhich is sent by the OLT through the ONU according to a downstream timeslice assigned by the OLT, and wherein the customer premises equipmentcomprises: a user side interface unit, configured to receive an upstreamsecond user side physical layer frame sent by a user or send adownstream second user side physical layer frame to the user; a virtualONU processor, configured to realize the ONU control plane function andthe PON MAC function, to encapsulate the upstream second user sidephysical layer frame into an upstream PON MAC layer frame, to send theupstream PON MAC layer frame to the ONU through a user side physicallayer processor according to the upstream time slice assigned by the OLTor receive, according to the downstream time slice assigned by the OLT,a downstream PON MAC layer frame sent by the user side physical layerprocessor, to convert the downstream PON MAC layer frame to thedownstream second user side physical layer frame, and to send thedownstream second user side physical layer frame to the user sidephysical layer processor through the user side interface unit; and theuser side physical layer processor, which is configured to convert theupstream PON MAC layer frame sent by the virtual ONU processor to anupstream first user side physical layer frame corresponding to anon-optical physical signal and to send the upstream first user sidephysical layer frame to the ONU through the non-optical physical signal,or to receive a downstream first user side physical layer frame sent bythe ONU, to convert the downstream first user side physical layer frameto the downstream PON MAC layer frame, and to send the downstream PONMAC layer frame to the virtual ONU processor.
 7. The customer premisesequipment according to claim 6, wherein the customer premises equipmentis further configured to receive a second physical layer parameter whichis delivered by the OLT through the ONU and to establish a newcommunication connection with the ONU according to the second physicallayer parameter delivered by the OLT.
 8. The customer premises equipmentaccording to claim 7, wherein the customer premises equipment is furtherconfigured to, before receiving the second physical layer parameterwhich is delivered by the OLT through the ONU, establish a communicationconnection with the ONU according to a default first physical layerparameter and establish a communication connection with the OLT, whereinthe default first physical layer parameter is reserved on the customerpremises equipment.
 9. An optical network unit (ONU), wherein the ONU isconnected to an optical line terminal (OLT) through an optical fiber,and is configured to: receive a signal according to one or both of thefollowing: receive a passive optical network (PON) physical layer framewhich is sent by the OLT through a PON physical signal, to convert thePON physical layer frame to a first user side physical layer framecorresponding to a non-optical physical signal, and to send the firstuser side physical layer frame to a customer premises equipment throughthe non-optical physical signal; and receive a first user side physicallayer frame which is sent by the customer premises equipment through thenon-optical physical signal, to convert the first user side physicallayer frame to a PON physical layer frame corresponding to the PONphysical signal, and to send the PON physical layer frame to the OLTthrough the PON physical signal; forward to the customer premisesequipment a second physical layer parameter delivered by the OLT and toestablish a new communication connection with the customer premisesequipment according to the second physical layer parameter delivered bythe OLT; and establish a communication connection with the customerpremises equipment according to a default first physical layer parameterbefore the customer premises equipment receives the second physicallayer parameter which is delivered by the OLT through the ONU, whereinthe default first physical layer parameter is reserved on the customerpremises equipment.
 10. The ONU according to claim 9, wherein the ONUcomprises: a non-optical physical layer processor; a switch controller;a switch; and a PON physical layer processor; wherein the non-opticalphysical layer processor is configured to receive an upstream first userside physical layer frame which is sent by the customer premisesequipment through the non-optical physical signal and to convert theupstream first user side physical layer frame to an upstream PON mediaaccess control (MAC) layer frame; wherein the switch controller isconfigured to, when receiving the upstream PON MAC layer frame sent bythe customer premises equipment, generate a switch control signalcorresponding to the customer premises equipment and to send the switchcontrol signal corresponding to the customer premises equipment to theswitch; wherein the switch comprises one output interface and at leastone input interface, wherein there is one-to-one correspondence betweenthe input interface and the customer premises equipment connected to theONU, and wherein the switch is configured to connect, according to theswitch control signal corresponding to the customer premises equipment,a channel between an input interface corresponding to the customerpremises equipment and an output interface, wherein the channel isconfigured for the non-optical physical layer processor to send theupstream PON MAC layer frame obtained through conversion by thenon-optical physical layer processor to the PON physical layerprocessor; and wherein the PON physical layer processor is configured toconvert the upstream PON MAC layer frame to an upstream PON physicallayer frame and to send the upstream PON physical layer frame to the OLTthrough the PON physical signal.
 11. The ONU according to claim 9,wherein the ONU comprises: a non-optical physical layer processor; anEthernet bridge; and a PON physical layer processor; wherein thenon-optical physical layer processor is configured to receive anupstream first user side physical layer frame which is sent by thecustomer premises equipment through the non-optical physical signal, toconvert the upstream first user side physical layer frame to an upstreamPON MAC layer frame, and to send the upstream PON MAC layer frame to theEthernet bridge through an input interface corresponding to thenon-optical physical layer processor; wherein the Ethernet bridgecomprises one output interface and at least one input interface andwherein the Ethernet bridge is configured to receive the upstream PONMAC layer frame which is sent by the non-optical physical layerprocessor through the input interface, to send the upstream PON MAClayer frame to the PON physical layer processor through the outputinterface; and to return an MAC address of an ONU physical adapter tothe customer premises equipment when the Ethernet bridge receives an ARP(Address Resolution Protocol) request from a user side; and wherein thePON physical layer processor is configured to receive the upstream PONMAC layer frame which is sent by the Ethernet bridge through the outputinterface, to convert the upstream PON MAC layer frame to the PONphysical layer frame, and to send the PON physical layer frame to theOLT through the PON physical signal.
 12. The ONU according to claim 9,wherein the ONU comprises: a PON physical layer processor: a non-opticalphysical layer processor; interfaces respectively corresponding tocustomer premises equipment connected to the ONU; and a downstream datareplicating unit, wherein the PON physical layer processor is configuredto receive a downstream PON physical layer frame which is sent by theOLT through the PON physical signal and to convert the downstream PONphysical layer frame to a downstream PON MAC layer frame; wherein theinterfaces are configured respectively to connect lines between thedownstream data replicating unit and the non-optical physical layerprocessor, wherein the lines are configured to send the downstream PONMAC layer frame obtained through conversion by the PON physical layerprocessor to the non-optical physical layer processor; wherein thedownstream data replicating unit is configured to replicate thedownstream PON MAC layer frame obtained through conversion by the PONphysical layer processor to all lines which belong to the ONU; andwherein the non-optical physical layer processor is configured toconvert the downstream PON MAC layer frame to a downstream first userside physical layer frame and to send the downstream first user sidephysical layer frame to the customer premises equipment through thenon-optical physical signal.